A straight chain organopolysiloxane-polyether block copolymer obtained by hydrosilylation reacting (1) an organopolysiloxane containing a SiH group on both terminals and (2) a polyether containing a methallyl group on both terminals is known as (AB)n type polyether-modified silicone (Patent Literature 1). Furthermore, Patent Literature 2 reports a method of manufacturing polyurethane foam using a non-hydrolyzable straight chain organopolysiloxane-polyether block copolymer having a high degree of polymerization as a foam stabilizing agent. However, only a toluene solution obtained as a result of performing a hydrosilylation reaction in a toluene solvent exists as an example of a composition containing the block copolymer. Toluene has high hazardous properties, flammability, and other risks, and therefore is removed from a manufacturing system by a stripping treatment under heating or reduced pressure conditions. Similarly, a xylene solution containing the block copolymer is known or commercialized, but similarly has a problem of including a flammable and hazardous organic solvent.
Furthermore, several reports have been made in relation to an application of the (AB)n type polyether-modified silicone (Patent Literatures 3 to 8). Patent Literatures 3 and 4 relate to a cosmetic containing the (AB)n type polyether-modified silicone, and disclose an example of adding to several cosmetic product formulations silicone after performing synthesis of the modified silicone in toluene and then removing the toluene similar to Patent Literatures 1 and 2. Furthermore, the present text describes that the copolymer is used independently or dissolved in water or various organic solvents. Similarly, Patent Literature 5 and Patent Literature 6 disclose a substance where the (AB)n type polyether-modified silicone is synthesized in toluene or other organic solvent, used as a foam stabilizer (foam stabilizing agent) of urethane foam, the toluene or the like must be removed from the manufacturing system by a stripping treatment. Note that in addition to disclosing an example where synthesis of the copolymer is performed in toluene, polypropylene glycol which is a diluting agent is added, and then the toluene is removed by a stripping operation, Patent Literature 6 mentions that polyols used in a urethane foam formulation can be used as a diluting agent. Furthermore, a commercially available foam stabilizer using a long chain alkylene benzene as a reaction solvent is described as a comparative example.
However, as described in Patent Literature 6, after a hydrosilylation is performed in toluene, when a polypropylene glycol as a diluting agent or derivative thereof is added, the toluene is removed by reduced pressure stripping, and solvent exchanging is performed, the (AB)n type polyether-modified silicone will have excellent foam stability, and therefore, air bubbles caught by stirring are fine and very stable, defoaming is suppressed, an upper space of a reactor is immediately filled with foam, and a pressure reduction operation must be very slowly and gradually performed. In other words, the manufacturing method is disadvantageous in industrial mass production. In contrast, Patent Literature 6 discloses a foam stabilizer that is synthesized by a long chain alkylene benzene and then used as is, but there is a problem where the non-reactive solvent remains in urethane foam migrates (oozes out) from the final product.
In other words, not only is there no description that a specific monool organic compound is used in the (AB)n type polyether-modified silicone solvent, and the advantages thereof are not suggested in Literatures 1 to 6, there are problems in industrial production processes, and thus sufficient performance cannot be achieved.
Herein, Patent Literature 7 relates to a hair cosmetic including a specific structure with a particularly high molecular weight of the (AB)n type polyether-modified silicones. Herein, examples of adding the structure to a large number of cosmetic formulations is disclosed, and in many of these formulations, an excess amount of dimethyl polysiloxane is combined with the structure. Patent Literature 8 relates to a straight oil agent for a fiber filamentous material including: a specific structure with a particularly high molecular weight of the (AB)n type polyether-modified silicones, and base oil formed from at least one type selected from diorganopolysiloxanes and mineral oils. With this application, continuous high speed processing of the fiber filamentous material is important in the process, and the viscosity of the oil agent must be kept low at a maximum of 100 mm2/s (and preferably 50 mm2/s) or lower. Therefore, in this example, a 10 mm2/s dimethyl polysiloxane is excessively mixed at over 40 times the structure and then used. In other words, the literatures only disclose a composition where dimethyl polysiloxane is excessively added to the (AB)n type polyether-modified silicone, and in each application, the dimethyl polysiloxane must be included at a large amount. In other words, there is no mention nor suggestion that the amount of dimethyl polysiloxane is at a constant level or lower and the advantages thereof, in the composition containing the (AB)n type polyether-modified silicone.
Similarly, Patent Literature 9 discloses a technique for stably manufacturing a copolymer with a particularly high molecular weight of the (AB)n type polyether-modified silicones or resembling structures, without causing increased viscosity, gelling, and the like. One of the examples describes synthesizing the copolymer in liquid isoparaffin (hydrogenated polyisobutene), and then distilling a low-boiling substance such as an unreacted substance by stripping (under heated and reduced pressure conditions). Furthermore, the present text describes several organic solvents and dimethyl polysiloxanes as a solvent that can be used in a hydrosilylation reacting step for synthesizing the copolymer. However, there is no mention nor suggestion that a specific monool organic compound is used in a solvent of the (AB)n type polyether-modified silicone, the amount of dimethyl polysiloxanes is at a constant level or lower in the composition, and the advantages thereof.
In other words, the compositions disclosed in Patent Literatures 1 to 9 are compositions that cannot be used in a surfactant or foam stabilizer of urethane, are inevitably disadvantageous in industrial production in a step of replacing a solvent obtained by synthesizing in an organic solvent with high toxicity such as toluene or the like with propylene glycol or the like, or have problems in performance as a foam stabilizer, and thus there is room for improvement in performance and manufacturing cost thereof. Therefore, the compositions are not sufficiently satisfactory for use as a surfactant or foam stabilizer, and thus had a problem where widespread adoption was hindered due to performance and cost.
On the other hand, Patent Literature 10 points out the importance of a surfactant with a high open cell effect in both hard foam and soft foam in open cell polyurethane foam and manufacturing process thereof, and points out the importance of controlling the open cell ratio even in the field of high density microcellular foam. However, Patent Literature 10 points out that a known (AB)n type polyether-modified silicone (=(AB)n copolymer) in the related art tends to form hydrogel in the presence of water, and therefore, use is limited. This is considered to indicate that a raw material composition for obtaining polyurethane foam has disadvantages of inferior storage stability of a so-called premixed solution formed from components other than isocyanate (including polyols, water, catalyst, and optionally, surfactants, and the like), and hard to be existing in a homogeneous condition for a long period of time.
The (AB)n type polyether-modified silicone can be designed to have an average molecular weight of a copolymer, and the surface activation performance, affinity to a urethane foam system, and the like can be controlled by the EO % or size of a polyether portion or by introducing a hydrophobic group or hydroxyl group to a terminal portion of a copolymer, and therefore is thought to be able to demonstrate an excellent effect as a surfactant for foam stabilization or foam control, in all polyurethane foam formulations other than high resilience foam which requires a foam stabilizer with a low molecular weight. In particular, the silicone is very useful in suppressing the open cell ratio required in recent years. However, known technology in the related art has the aforementioned problems with performance, manufacturing problems directly linked to industrial production cost, problems with application, and problems such as insufficient penetration into the market regardless of potential value due to these factors. Therefore, development is desired for a new composition containing the (AB)n type polyether-modified silicone having sufficient usefulness in applications such as surfactants, foam stabilizers, and the like, which can resolve the plurality of problems and be supplied into the market in a larger amount and lower cost than in the related art.